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<a name="1" href="#1">1</a>   <em class="comment">/*</em>
<a name="2" href="#2">2</a>   <em class="comment"> * $Header$</em>
<a name="3" href="#3">3</a>   <em class="comment"> * $Revision: 1321 $</em>
<a name="4" href="#4">4</a>   <em class="comment"> * $Date: 2008-04-26 17:30:06 -0700 (Sat, 26 Apr 2008) $</em>
<a name="5" href="#5">5</a>   <em class="comment"> *</em>
<a name="6" href="#6">6</a>   <em class="comment"> * ====================================================================</em>
<a name="7" href="#7">7</a>   <em class="comment"> *</em>
<a name="8" href="#8">8</a>   <em class="comment"> * Copyright 2000-2002 bob mcwhirter &amp; James Strachan.</em>
<a name="9" href="#9">9</a>   <em class="comment"> * All rights reserved.</em>
<a name="10" href="#10">10</a>  <em class="comment"> *</em>
<a name="11" href="#11">11</a>  <em class="comment"> * Redistribution and use in source and binary forms, with or without</em>
<a name="12" href="#12">12</a>  <em class="comment"> * modification, are permitted provided that the following conditions are</em>
<a name="13" href="#13">13</a>  <em class="comment"> * met:</em>
<a name="14" href="#14">14</a>  <em class="comment"> * </em>
<a name="15" href="#15">15</a>  <em class="comment"> *   * Redistributions of source code must retain the above copyright</em>
<a name="16" href="#16">16</a>  <em class="comment"> *     notice, this list of conditions and the following disclaimer.</em>
<a name="17" href="#17">17</a>  <em class="comment"> * </em>
<a name="18" href="#18">18</a>  <em class="comment"> *   * Redistributions in binary form must reproduce the above copyright</em>
<a name="19" href="#19">19</a>  <em class="comment"> *     notice, this list of conditions and the following disclaimer in the</em>
<a name="20" href="#20">20</a>  <em class="comment"> *     documentation and/or other materials provided with the distribution.</em>
<a name="21" href="#21">21</a>  <em class="comment"> * </em>
<a name="22" href="#22">22</a>  <em class="comment"> *   * Neither the name of the Jaxen Project nor the names of its</em>
<a name="23" href="#23">23</a>  <em class="comment"> *     contributors may be used to endorse or promote products derived </em>
<a name="24" href="#24">24</a>  <em class="comment"> *     from this software without specific prior written permission.</em>
<a name="25" href="#25">25</a>  <em class="comment"> * </em>
<a name="26" href="#26">26</a>  <em class="comment"> * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS</em>
<a name="27" href="#27">27</a>  <em class="comment"> * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED</em>
<a name="28" href="#28">28</a>  <em class="comment"> * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A</em>
<a name="29" href="#29">29</a>  <em class="comment"> * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER</em>
<a name="30" href="#30">30</a>  <em class="comment"> * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,</em>
<a name="31" href="#31">31</a>  <em class="comment"> * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,</em>
<a name="32" href="#32">32</a>  <em class="comment"> * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR</em>
<a name="33" href="#33">33</a>  <em class="comment"> * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF</em>
<a name="34" href="#34">34</a>  <em class="comment"> * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING</em>
<a name="35" href="#35">35</a>  <em class="comment"> * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS</em>
<a name="36" href="#36">36</a>  <em class="comment"> * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.</em>
<a name="37" href="#37">37</a>  <em class="comment"> *</em>
<a name="38" href="#38">38</a>  <em class="comment"> * ====================================================================</em>
<a name="39" href="#39">39</a>  <em class="comment"> * This software consists of voluntary contributions made by many </em>
<a name="40" href="#40">40</a>  <em class="comment"> * individuals on behalf of the Jaxen Project and was originally </em>
<a name="41" href="#41">41</a>  <em class="comment"> * created by bob mcwhirter &lt;bob@werken.com> and </em>
<a name="42" href="#42">42</a>  <em class="comment"> * James Strachan &lt;jstrachan@apache.org>.  For more information on the </em>
<a name="43" href="#43">43</a>  <em class="comment"> * Jaxen Project, please see &lt;<a href="http://www.jaxen.org/" target="alexandria_uri">http://www.jaxen.org/</a>>.</em>
<a name="44" href="#44">44</a>  <em class="comment"> * </em>
<a name="45" href="#45">45</a>  <em class="comment"> * $Id: BaseXPath.java 1321 2008-04-27 00:30:06Z elharo $</em>
<a name="46" href="#46">46</a>  <em class="comment"> */</em>
<a name="47" href="#47">47</a>  
<a name="48" href="#48">48</a>  
<a name="49" href="#49">49</a>  <strong>package</strong> org.jaxen;
<a name="50" href="#50">50</a>  
<a name="51" href="#51">51</a>  <strong>import</strong> java.io.Serializable;
<a name="52" href="#52">52</a>  <strong>import</strong> java.util.List;
<a name="53" href="#53">53</a>  
<a name="54" href="#54">54</a>  <strong>import</strong> org.jaxen.expr.Expr;
<a name="55" href="#55">55</a>  <strong>import</strong> org.jaxen.expr.XPathExpr;
<a name="56" href="#56">56</a>  <strong>import</strong> org.jaxen.function.BooleanFunction;
<a name="57" href="#57">57</a>  <strong>import</strong> org.jaxen.function.NumberFunction;
<a name="58" href="#58">58</a>  <strong>import</strong> org.jaxen.function.StringFunction;
<a name="59" href="#59">59</a>  <strong>import</strong> org.jaxen.saxpath.SAXPathException;
<a name="60" href="#60">60</a>  <strong>import</strong> org.jaxen.saxpath.XPathReader;
<a name="61" href="#61">61</a>  <strong>import</strong> org.jaxen.saxpath.helpers.XPathReaderFactory;
<a name="62" href="#62">62</a>  <strong>import</strong> org.jaxen.util.SingletonList;
<a name="63" href="#63">63</a>  
<a name="64" href="#64">64</a>  <em>/**</em><em> Base functionality for all concrete, implementation-specific XPaths.</em>
<a name="65" href="#65">65</a>  <em> *</em>
<a name="66" href="#66">66</a>  <em> *  &lt;p></em>
<a name="67" href="#67">67</a>  <em> *  This class provides generic functionality for further-defined</em>
<a name="68" href="#68">68</a>  <em> *  implementation-specific XPaths.</em>
<a name="69" href="#69">69</a>  <em> *  &lt;/p></em>
<a name="70" href="#70">70</a>  <em> *</em>
<a name="71" href="#71">71</a>  <em> *  &lt;p></em>
<a name="72" href="#72">72</a>  <em> *  If you want to adapt the Jaxen engine so that it can traverse your own</em>
<a name="73" href="#73">73</a>  <em> *  object model, then this is a good base class to derive from.</em>
<a name="74" href="#74">74</a>  <em> *  Typically you only really need to provide your own </em>
<a name="75" href="#75">75</a>  <em> *  {@link org.jaxen.Navigator} implementation.</em>
<a name="76" href="#76">76</a>  <em> *  &lt;/p></em>
<a name="77" href="#77">77</a>  <em> *</em>
<a name="78" href="#78">78</a>  <em> *  @see org.jaxen.dom4j.Dom4jXPath XPath for dom4j</em>
<a name="79" href="#79">79</a>  <em> *  @see org.jaxen.jdom.JDOMXPath   XPath for JDOM</em>
<a name="80" href="#80">80</a>  <em> *  @see org.jaxen.dom.DOMXPath     XPath for W3C DOM</em>
<a name="81" href="#81">81</a>  <em> *</em>
<a name="82" href="#82">82</a>  <em> *  @author &lt;a href="<a href="mailto:bob@werken.com" target="alexandria_uri">mailto:bob@werken.com</a>">bob mcwhirter&lt;/a></em>
<a name="83" href="#83">83</a>  <em> *  @author &lt;a href="<a href="mailto:jstrachan@apache.org" target="alexandria_uri">mailto:jstrachan@apache.org</a>">James Strachan&lt;/a></em>
<a name="84" href="#84">84</a>  <em> */</em>
<a name="85" href="#85">85</a>  <strong>public</strong> <strong>class</strong> <a href="../../org/jaxen/BaseXPath.html">BaseXPath</a> implements XPath, Serializable
<a name="86" href="#86">86</a>  {
<a name="87" href="#87">87</a>  
<a name="88" href="#88">88</a>      <strong>private</strong> <strong>static</strong> <strong>final</strong> <strong>long</strong> serialVersionUID = -1993731281300293168L;
<a name="89" href="#89">89</a>  
<a name="90" href="#90">90</a>      <em>/**</em><em> Original expression text. */</em>
<a name="91" href="#91">91</a>      <strong>private</strong> <strong>final</strong> String exprText;
<a name="92" href="#92">92</a>  
<a name="93" href="#93">93</a>      <em>/**</em><em> the parsed form of the <a href="../../org/jaxen/XPath.html">XPath</a> expression */</em>
<a name="94" href="#94">94</a>      <strong>private</strong> <strong>final</strong> <a href="../../org/jaxen/expr/XPathExpr.html">XPathExpr</a> xpath;
<a name="95" href="#95">95</a>      
<a name="96" href="#96">96</a>      <em>/**</em><em> the support information and function, namespace and variable contexts */</em>
<a name="97" href="#97">97</a>      <strong>private</strong> <a href="../../org/jaxen/ContextSupport.html">ContextSupport</a> support;
<a name="98" href="#98">98</a>  
<a name="99" href="#99">99</a>      <em>/**</em><em> the implementation-specific <a href="../../org/jaxen/Navigator.html">Navigator</a> for retrieving XML nodes **/</em>
<a name="100" href="#100">100</a>     <strong>private</strong> <a href="../../org/jaxen/Navigator.html">Navigator</a> navigator;
<a name="101" href="#101">101</a>     
<a name="102" href="#102">102</a>     <em>/**</em><em> Construct given an XPath expression string. </em>
<a name="103" href="#103">103</a> <em>     *</em>
<a name="104" href="#104">104</a> <em>     *  @param xpathExpr the XPath expression</em>
<a name="105" href="#105">105</a> <em>     *</em>
<a name="106" href="#106">106</a> <em>     *  @throws JaxenException if there is a syntax error while</em>
<a name="107" href="#107">107</a> <em>     *          parsing the expression</em>
<a name="108" href="#108">108</a> <em>     */</em>
<a name="109" href="#109">109</a>     <strong>protected</strong> <a href="../../org/jaxen/BaseXPath.html">BaseXPath</a>(String xpathExpr) throws JaxenException
<a name="110" href="#110">110</a>     {
<a name="111" href="#111">111</a>         <strong>try</strong>
<a name="112" href="#112">112</a>         {
<a name="113" href="#113">113</a>             <a href="../../org/jaxen/saxpath/XPathReader.html">XPathReader</a> reader = XPathReaderFactory.createReader();
<a name="114" href="#114">114</a>             <a href="../../org/jaxen/JaxenHandler.html">JaxenHandler</a> handler = <strong>new</strong> <a href="../../org/jaxen/JaxenHandler.html">JaxenHandler</a>();
<a name="115" href="#115">115</a>             reader.setXPathHandler( handler );
<a name="116" href="#116">116</a>             reader.parse( xpathExpr );
<a name="117" href="#117">117</a>             <strong>this</strong>.xpath = handler.getXPathExpr();
<a name="118" href="#118">118</a>         }
<a name="119" href="#119">119</a>         <strong>catch</strong> (org.jaxen.saxpath.XPathSyntaxException e)
<a name="120" href="#120">120</a>         {
<a name="121" href="#121">121</a>             <strong>throw</strong> <strong>new</strong> org.jaxen.XPathSyntaxException( e );
<a name="122" href="#122">122</a>         }
<a name="123" href="#123">123</a>         <strong>catch</strong> (SAXPathException e)
<a name="124" href="#124">124</a>         {
<a name="125" href="#125">125</a>             <strong>throw</strong> <strong>new</strong> <a href="../../org/jaxen/JaxenException.html">JaxenException</a>( e );
<a name="126" href="#126">126</a>         }
<a name="127" href="#127">127</a> 
<a name="128" href="#128">128</a>         <strong>this</strong>.exprText = xpathExpr;
<a name="129" href="#129">129</a>     }
<a name="130" href="#130">130</a> 
<a name="131" href="#131">131</a>     <em>/**</em><em> Construct given an XPath expression string.</em>
<a name="132" href="#132">132</a> <em>     *</em>
<a name="133" href="#133">133</a> <em>     *  @param xpathExpr the XPath expression</em>
<a name="134" href="#134">134</a> <em>     *</em>
<a name="135" href="#135">135</a> <em>     *  @param navigator the XML navigator to use</em>
<a name="136" href="#136">136</a> <em>     *</em>
<a name="137" href="#137">137</a> <em>     *  @throws JaxenException if there is a syntax error while</em>
<a name="138" href="#138">138</a> <em>     *          parsing the expression</em>
<a name="139" href="#139">139</a> <em>     */</em>
<a name="140" href="#140">140</a>     <strong>public</strong> <a href="../../org/jaxen/BaseXPath.html">BaseXPath</a>(String xpathExpr, <a href="../../org/jaxen/Navigator.html">Navigator</a> navigator) throws JaxenException
<a name="141" href="#141">141</a>     {
<a name="142" href="#142">142</a>         <strong>this</strong>( xpathExpr );
<a name="143" href="#143">143</a>         <strong>this</strong>.navigator = navigator;
<a name="144" href="#144">144</a>     }
<a name="145" href="#145">145</a> 
<a name="146" href="#146">146</a>     <em>/**</em><em> Evaluate this XPath against a given context.</em>
<a name="147" href="#147">147</a> <em>     *  The context of evaluation may be any object type</em>
<a name="148" href="#148">148</a> <em>     *  the navigator recognizes as a node.</em>
<a name="149" href="#149">149</a> <em>     *  The return value is either a &lt;code>String&lt;/code>,</em>
<a name="150" href="#150">150</a> <em>     *  &lt;code>Double&lt;/code>, &lt;code>Boolean&lt;/code>, or &lt;code>List&lt;/code></em>
<a name="151" href="#151">151</a> <em>     *  of nodes.</em>
<a name="152" href="#152">152</a> <em>     *</em>
<a name="153" href="#153">153</a> <em>     *  &lt;p></em>
<a name="154" href="#154">154</a> <em>     *  When using this method, one must be careful to</em>
<a name="155" href="#155">155</a> <em>     *  test the class of the returned object.  If the returned </em>
<a name="156" href="#156">156</a> <em>     *  object is a list, then the items in this </em>
<a name="157" href="#157">157</a> <em>     *  list will be the actual &lt;code>Document&lt;/code>,</em>
<a name="158" href="#158">158</a> <em>     *  &lt;code>Element&lt;/code>, &lt;code>Attribute&lt;/code>, etc. objects</em>
<a name="159" href="#159">159</a> <em>     *  as defined by the concrete XML object-model implementation,</em>
<a name="160" href="#160">160</a> <em>     *  directly from the context document.  This method &lt;strong>does</em>
<a name="161" href="#161">161</a> <em>     *  not return &lt;em>copies&lt;/em> of anything&lt;/strong>, but merely </em>
<a name="162" href="#162">162</a> <em>     *  returns references to objects within the source document.</em>
<a name="163" href="#163">163</a> <em>     *  &lt;/p></em>
<a name="164" href="#164">164</a> <em>     *  </em>
<a name="165" href="#165">165</a> <em>     * @param context the node, node-set or Context object for evaluation. </em>
<a name="166" href="#166">166</a> <em>     *      This value can be null.</em>
<a name="167" href="#167">167</a> <em>     *</em>
<a name="168" href="#168">168</a> <em>     * @return the result of evaluating the XPath expression</em>
<a name="169" href="#169">169</a> <em>     *          against the supplied context</em>
<a name="170" href="#170">170</a> <em>     * @throws JaxenException if an XPath error occurs during expression evaluation</em>
<a name="171" href="#171">171</a> <em>     * @throws ClassCastException if the context is not a node</em>
<a name="172" href="#172">172</a> <em>     */</em>
<a name="173" href="#173">173</a>     <strong>public</strong> Object evaluate(Object context) throws JaxenException
<a name="174" href="#174">174</a>     {
<a name="175" href="#175">175</a>         List answer = selectNodes(context);
<a name="176" href="#176">176</a> 
<a name="177" href="#177">177</a>         <strong>if</strong> ( answer != <strong>null</strong>
<a name="178" href="#178">178</a>              &amp;&amp;
<a name="179" href="#179">179</a>              answer.size() == 1 )
<a name="180" href="#180">180</a>         {
<a name="181" href="#181">181</a>             Object first = answer.get(0);
<a name="182" href="#182">182</a> 
<a name="183" href="#183">183</a>             <strong>if</strong> ( first instanceof String
<a name="184" href="#184">184</a>                  ||
<a name="185" href="#185">185</a>                  first instanceof Number
<a name="186" href="#186">186</a>                  ||
<a name="187" href="#187">187</a>                  first instanceof Boolean ) 
<a name="188" href="#188">188</a>             {
<a name="189" href="#189">189</a>                 <strong>return</strong> first;
<a name="190" href="#190">190</a>             }
<a name="191" href="#191">191</a>         }
<a name="192" href="#192">192</a>         <strong>return</strong> answer;
<a name="193" href="#193">193</a>     }
<a name="194" href="#194">194</a>     
<a name="195" href="#195">195</a>     <em>/**</em><em> Select all nodes that are selected by this XPath</em>
<a name="196" href="#196">196</a> <em>     *  expression. If multiple nodes match, multiple nodes</em>
<a name="197" href="#197">197</a> <em>     *  will be returned. Nodes will be returned</em>
<a name="198" href="#198">198</a> <em>     *  in document-order, as defined by the XPath</em>
<a name="199" href="#199">199</a> <em>     *  specification. If the expression selects a non-node-set</em>
<a name="200" href="#200">200</a> <em>     *  (i.e. a number, boolean, or string) then a List</em>
<a name="201" href="#201">201</a> <em>     *  containing just that one object is returned.</em>
<a name="202" href="#202">202</a> <em>     *  &lt;/p></em>
<a name="203" href="#203">203</a> <em>     *</em>
<a name="204" href="#204">204</a> <em>     * @param node the node, node-set or Context object for evaluation. </em>
<a name="205" href="#205">205</a> <em>     *     This value can be null.</em>
<a name="206" href="#206">206</a> <em>     *</em>
<a name="207" href="#207">207</a> <em>     * @return the node-set of all items selected</em>
<a name="208" href="#208">208</a> <em>     *          by this XPath expression</em>
<a name="209" href="#209">209</a> <em>     * @throws JaxenException if an XPath error occurs during expression evaluation</em>
<a name="210" href="#210">210</a> <em>     *</em>
<a name="211" href="#211">211</a> <em>     * @see #selectNodesForContext</em>
<a name="212" href="#212">212</a> <em>     */</em>
<a name="213" href="#213">213</a>     <strong>public</strong> List selectNodes(Object node) throws JaxenException
<a name="214" href="#214">214</a>     {
<a name="215" href="#215">215</a>         <a href="../../org/jaxen/Context.html">Context</a> context = getContext( node );
<a name="216" href="#216">216</a>         <strong>return</strong> selectNodesForContext( context );
<a name="217" href="#217">217</a>     }
<a name="218" href="#218">218</a> 
<a name="219" href="#219">219</a>     <em>/**</em><em> Select only the first node selected by this XPath</em>
<a name="220" href="#220">220</a> <em>     *  expression.  If multiple nodes match, only one node will be</em>
<a name="221" href="#221">221</a> <em>     *  returned. The selected node will be the first</em>
<a name="222" href="#222">222</a> <em>     *  selected node in document-order, as defined by the XPath</em>
<a name="223" href="#223">223</a> <em>     *  specification.</em>
<a name="224" href="#224">224</a> <em>     *  &lt;/p></em>
<a name="225" href="#225">225</a> <em>     *</em>
<a name="226" href="#226">226</a> <em>     * @param node the node, node-set or Context object for evaluation. </em>
<a name="227" href="#227">227</a> <em>     *     This value can be null.</em>
<a name="228" href="#228">228</a> <em>     *</em>
<a name="229" href="#229">229</a> <em>     * @return the node-set of all items selected</em>
<a name="230" href="#230">230</a> <em>     *          by this XPath expression</em>
<a name="231" href="#231">231</a> <em>     * @throws JaxenException if an XPath error occurs during expression evaluation</em>
<a name="232" href="#232">232</a> <em>     *</em>
<a name="233" href="#233">233</a> <em>     * @see #selectNodes</em>
<a name="234" href="#234">234</a> <em>     */</em>
<a name="235" href="#235">235</a>     <strong>public</strong> Object selectSingleNode(Object node) throws JaxenException
<a name="236" href="#236">236</a>     {
<a name="237" href="#237">237</a>         List results = selectNodes( node );
<a name="238" href="#238">238</a> 
<a name="239" href="#239">239</a>         <strong>if</strong> ( results.isEmpty() )
<a name="240" href="#240">240</a>         {
<a name="241" href="#241">241</a>             <strong>return</strong> <strong>null</strong>;
<a name="242" href="#242">242</a>         }
<a name="243" href="#243">243</a> 
<a name="244" href="#244">244</a>         <strong>return</strong> results.get( 0 );
<a name="245" href="#245">245</a>     }
<a name="246" href="#246">246</a> 
<a name="247" href="#247">247</a>     <em>/**</em>
<a name="248" href="#248">248</a> <em>     * Returns the XPath string-value of the argument node.</em>
<a name="249" href="#249">249</a> <em>     * </em>
<a name="250" href="#250">250</a> <em>     * @param node the node whose value to take</em>
<a name="251" href="#251">251</a> <em>     * @return the XPath string value of this node</em>
<a name="252" href="#252">252</a> <em>     * @throws JaxenException if an XPath error occurs during expression evaluation</em>
<a name="253" href="#253">253</a> <em>     * @deprecated replaced by {@link #stringValueOf}</em>
<a name="254" href="#254">254</a> <em>     */</em>
<a name="255" href="#255">255</a>     <strong>public</strong> String valueOf(Object node) throws JaxenException
<a name="256" href="#256">256</a>     {
<a name="257" href="#257">257</a>         <strong>return</strong> stringValueOf( node );
<a name="258" href="#258">258</a>     }
<a name="259" href="#259">259</a> 
<a name="260" href="#260">260</a>     <em>/**</em><em> Retrieves the string-value of the result of</em>
<a name="261" href="#261">261</a> <em>     *  evaluating this XPath expression when evaluated </em>
<a name="262" href="#262">262</a> <em>     *  against the specified context.</em>
<a name="263" href="#263">263</a> <em>     *</em>
<a name="264" href="#264">264</a> <em>     *  &lt;p></em>
<a name="265" href="#265">265</a> <em>     *  The string-value of the expression is determined per</em>
<a name="266" href="#266">266</a> <em>     *  the &lt;code>string(..)&lt;/code> core function defined</em>
<a name="267" href="#267">267</a> <em>     *  in the XPath specification.  This means that an expression</em>
<a name="268" href="#268">268</a> <em>     *  that selects zero nodes will return the empty string,</em>
<a name="269" href="#269">269</a> <em>     *  while an expression that selects one-or-more nodes will</em>
<a name="270" href="#270">270</a> <em>     *  return the string-value of the first node.</em>
<a name="271" href="#271">271</a> <em>     *  &lt;/p></em>
<a name="272" href="#272">272</a> <em>     *</em>
<a name="273" href="#273">273</a> <em>     * @param node the node, node-set or Context object for evaluation. This value can be null.</em>
<a name="274" href="#274">274</a> <em>     *</em>
<a name="275" href="#275">275</a> <em>     * @return the string-value of the result of evaluating this expression with the specified context node</em>
<a name="276" href="#276">276</a> <em>     * @throws JaxenException if an XPath error occurs during expression evaluation</em>
<a name="277" href="#277">277</a> <em>     */</em>
<a name="278" href="#278">278</a>     <strong>public</strong> String stringValueOf(Object node) throws JaxenException
<a name="279" href="#279">279</a>     {
<a name="280" href="#280">280</a>         <a href="../../org/jaxen/Context.html">Context</a> context = getContext( node );
<a name="281" href="#281">281</a>         
<a name="282" href="#282">282</a>         Object result = selectSingleNodeForContext( context );
<a name="283" href="#283">283</a> 
<a name="284" href="#284">284</a>         <strong>if</strong> ( result == <strong>null</strong> )
<a name="285" href="#285">285</a>         {
<a name="286" href="#286">286</a>             <strong>return</strong> <span class="string">""</span>;
<a name="287" href="#287">287</a>         }
<a name="288" href="#288">288</a> 
<a name="289" href="#289">289</a>         <strong>return</strong> StringFunction.evaluate( result,
<a name="290" href="#290">290</a>                                         context.getNavigator() );
<a name="291" href="#291">291</a>     }
<a name="292" href="#292">292</a> 
<a name="293" href="#293">293</a>     <em>/**</em><em> Retrieve a boolean-value interpretation of this XPath</em>
<a name="294" href="#294">294</a> <em>     *  expression when evaluated against a given context.</em>
<a name="295" href="#295">295</a> <em>     *</em>
<a name="296" href="#296">296</a> <em>     *  &lt;p></em>
<a name="297" href="#297">297</a> <em>     *  The boolean-value of the expression is determined per</em>
<a name="298" href="#298">298</a> <em>     *  the &lt;code>boolean(..)&lt;/code> function defined</em>
<a name="299" href="#299">299</a> <em>     *  in the XPath specification.  This means that an expression</em>
<a name="300" href="#300">300</a> <em>     *  that selects zero nodes will return &lt;code>false&lt;/code>,</em>
<a name="301" href="#301">301</a> <em>     *  while an expression that selects one or more nodes will</em>
<a name="302" href="#302">302</a> <em>     *  return &lt;code>true&lt;/code>.</em>
<a name="303" href="#303">303</a> <em>     *  &lt;/p></em>
<a name="304" href="#304">304</a> <em>     *</em>
<a name="305" href="#305">305</a> <em>     * @param node the node, node-set or Context object for evaluation. This value can be null.</em>
<a name="306" href="#306">306</a> <em>     *</em>
<a name="307" href="#307">307</a> <em>     * @return the boolean-value of the result of evaluating this expression with the specified context node</em>
<a name="308" href="#308">308</a> <em>     * @throws JaxenException if an XPath error occurs during expression evaluation</em>
<a name="309" href="#309">309</a> <em>     */</em>
<a name="310" href="#310">310</a>     <strong>public</strong> <strong>boolean</strong> <strong>boolean</strong>ValueOf(Object node) throws JaxenException
<a name="311" href="#311">311</a>     {
<a name="312" href="#312">312</a>         <a href="../../org/jaxen/Context.html">Context</a> context = getContext( node );
<a name="313" href="#313">313</a>         List result = selectNodesForContext( context );
<a name="314" href="#314">314</a>         <strong>if</strong> ( result == <strong>null</strong> ) <strong>return</strong> false;
<a name="315" href="#315">315</a>         <strong>return</strong> BooleanFunction.evaluate( result, context.getNavigator() ).booleanValue();
<a name="316" href="#316">316</a>     }
<a name="317" href="#317">317</a> 
<a name="318" href="#318">318</a>     <em>/**</em><em> Retrieve a number-value interpretation of this XPath</em>
<a name="319" href="#319">319</a> <em>     *  expression when evaluated against a given context.</em>
<a name="320" href="#320">320</a> <em>     *</em>
<a name="321" href="#321">321</a> <em>     *  &lt;p></em>
<a name="322" href="#322">322</a> <em>     *  The number-value of the expression is determined per</em>
<a name="323" href="#323">323</a> <em>     *  the &lt;code>number(..)&lt;/code> core function as defined</em>
<a name="324" href="#324">324</a> <em>     *  in the XPath specification. This means that if this</em>
<a name="325" href="#325">325</a> <em>     *  expression selects multiple nodes, the number-value</em>
<a name="326" href="#326">326</a> <em>     *  of the first node is returned.</em>
<a name="327" href="#327">327</a> <em>     *  &lt;/p></em>
<a name="328" href="#328">328</a> <em>     *</em>
<a name="329" href="#329">329</a> <em>     * @param node the node, node-set or Context object for evaluation. This value can be null.</em>
<a name="330" href="#330">330</a> <em>     *</em>
<a name="331" href="#331">331</a> <em>     * @return a &lt;code>Double&lt;/code> indicating the numeric value of</em>
<a name="332" href="#332">332</a> <em>     *      evaluating this expression against the specified context</em>
<a name="333" href="#333">333</a> <em>     * @throws JaxenException if an XPath error occurs during expression evaluation</em>
<a name="334" href="#334">334</a> <em>     */</em>
<a name="335" href="#335">335</a>     <strong>public</strong> Number numberValueOf(Object node) throws JaxenException
<a name="336" href="#336">336</a>     {
<a name="337" href="#337">337</a>         <a href="../../org/jaxen/Context.html">Context</a> context = getContext( node );
<a name="338" href="#338">338</a>         Object result = selectSingleNodeForContext( context );
<a name="339" href="#339">339</a>         <strong>return</strong> NumberFunction.evaluate( result,
<a name="340" href="#340">340</a>                                         context.getNavigator() );
<a name="341" href="#341">341</a>     }
<a name="342" href="#342">342</a> 
<a name="343" href="#343">343</a>     <em class="comment">// Helpers</em>
<a name="344" href="#344">344</a> 
<a name="345" href="#345">345</a>     <em>/**</em><em> Add a namespace prefix-to-URI mapping for this XPath</em>
<a name="346" href="#346">346</a> <em>     *  expression.</em>
<a name="347" href="#347">347</a> <em>     *</em>
<a name="348" href="#348">348</a> <em>     *  &lt;p></em>
<a name="349" href="#349">349</a> <em>     *  Namespace prefix-to-URI mappings in an XPath are independent</em>
<a name="350" href="#350">350</a> <em>     *  of those used within any document.  Only the mapping explicitly</em>
<a name="351" href="#351">351</a> <em>     *  added to this XPath will be available for resolving the</em>
<a name="352" href="#352">352</a> <em>     *  XPath expression.</em>
<a name="353" href="#353">353</a> <em>     *  &lt;/p></em>
<a name="354" href="#354">354</a> <em>     *</em>
<a name="355" href="#355">355</a> <em>     *  &lt;p></em>
<a name="356" href="#356">356</a> <em>     *  This is a convenience method for adding mappings to the</em>
<a name="357" href="#357">357</a> <em>     *  default {@link NamespaceContext} in place for this XPath.</em>
<a name="358" href="#358">358</a> <em>     *  If you have installed a custom &lt;code>NamespaceContext&lt;/code></em>
<a name="359" href="#359">359</a> <em>     *  that is not a &lt;code>SimpleNamespaceContext&lt;/code>,</em>
<a name="360" href="#360">360</a> <em>     *  then this method will throw a &lt;code>JaxenException&lt;/code>.</em>
<a name="361" href="#361">361</a> <em>     *  &lt;/p></em>
<a name="362" href="#362">362</a> <em>     *</em>
<a name="363" href="#363">363</a> <em>     *  @param prefix the namespace prefix</em>
<a name="364" href="#364">364</a> <em>     *  @param uri the namespace URI</em>
<a name="365" href="#365">365</a> <em>     *</em>
<a name="366" href="#366">366</a> <em>     *  @throws JaxenException if the &lt;code>NamespaceContext&lt;/code></em>
<a name="367" href="#367">367</a> <em>     *          used by this XPath is not a &lt;code>SimpleNamespaceContext&lt;/code></em>
<a name="368" href="#368">368</a> <em>     */</em>
<a name="369" href="#369">369</a>     <strong>public</strong> <strong>void</strong> addNamespace(String prefix,
<a name="370" href="#370">370</a>                              String uri) throws JaxenException
<a name="371" href="#371">371</a>     {
<a name="372" href="#372">372</a>         <a href="../../org/jaxen/NamespaceContext.html">NamespaceContext</a> nsContext = getNamespaceContext();
<a name="373" href="#373">373</a>         <strong>if</strong> ( nsContext instanceof SimpleNamespaceContext )
<a name="374" href="#374">374</a>         {
<a name="375" href="#375">375</a>             ((<a href="../../org/jaxen/SimpleNamespaceContext.html">SimpleNamespaceContext</a>)nsContext).addNamespace( prefix,
<a name="376" href="#376">376</a>                                                               uri );
<a name="377" href="#377">377</a>             <strong>return</strong>;
<a name="378" href="#378">378</a>         }
<a name="379" href="#379">379</a> 
<a name="380" href="#380">380</a>         <strong>throw</strong> <strong>new</strong> <a href="../../org/jaxen/JaxenException.html">JaxenException</a>(<span class="string">"Operation not permitted while using a non-simple namespace context."</span>);
<a name="381" href="#381">381</a>     }
<a name="382" href="#382">382</a> 
<a name="383" href="#383">383</a> 
<a name="384" href="#384">384</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="385" href="#385">385</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="386" href="#386">386</a>     <em class="comment">//     Properties</em>
<a name="387" href="#387">387</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="388" href="#388">388</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="389" href="#389">389</a> 
<a name="390" href="#390">390</a>     
<a name="391" href="#391">391</a>     <em>/**</em><em> Set a &lt;code>NamespaceContext&lt;/code> for use with this</em>
<a name="392" href="#392">392</a> <em>     *  XPath expression.</em>
<a name="393" href="#393">393</a> <em>     *</em>
<a name="394" href="#394">394</a> <em>     *  &lt;p></em>
<a name="395" href="#395">395</a> <em>     *  A &lt;code>NamespaceContext&lt;/code> is responsible for translating</em>
<a name="396" href="#396">396</a> <em>     *  namespace prefixes within the expression into namespace URIs.</em>
<a name="397" href="#397">397</a> <em>     *  &lt;/p></em>
<a name="398" href="#398">398</a> <em>     *</em>
<a name="399" href="#399">399</a> <em>     *  @param namespaceContext the &lt;code>NamespaceContext&lt;/code> to</em>
<a name="400" href="#400">400</a> <em>     *         install for this expression</em>
<a name="401" href="#401">401</a> <em>     *</em>
<a name="402" href="#402">402</a> <em>     *  @see NamespaceContext</em>
<a name="403" href="#403">403</a> <em>     *  @see NamespaceContext#translateNamespacePrefixToUri</em>
<a name="404" href="#404">404</a> <em>     */</em>
<a name="405" href="#405">405</a>     <strong>public</strong> <strong>void</strong> setNamespaceContext(<a href="../../org/jaxen/NamespaceContext.html">NamespaceContext</a> namespaceContext)
<a name="406" href="#406">406</a>     {
<a name="407" href="#407">407</a>         getContextSupport().setNamespaceContext(namespaceContext);
<a name="408" href="#408">408</a>     }
<a name="409" href="#409">409</a> 
<a name="410" href="#410">410</a>     <em>/**</em><em> Set a &lt;code>FunctionContext&lt;/code> for use with this XPath</em>
<a name="411" href="#411">411</a> <em>     *  expression.</em>
<a name="412" href="#412">412</a> <em>     *</em>
<a name="413" href="#413">413</a> <em>     *  &lt;p></em>
<a name="414" href="#414">414</a> <em>     *  A &lt;code>FunctionContext&lt;/code> is responsible for resolving</em>
<a name="415" href="#415">415</a> <em>     *  all function calls used within the expression.</em>
<a name="416" href="#416">416</a> <em>     *  &lt;/p></em>
<a name="417" href="#417">417</a> <em>     *</em>
<a name="418" href="#418">418</a> <em>     *  @param functionContext the &lt;code>FunctionContext&lt;/code> to</em>
<a name="419" href="#419">419</a> <em>     *         install for this expression</em>
<a name="420" href="#420">420</a> <em>     *</em>
<a name="421" href="#421">421</a> <em>     *  @see FunctionContext</em>
<a name="422" href="#422">422</a> <em>     *  @see FunctionContext#getFunction</em>
<a name="423" href="#423">423</a> <em>     */</em>
<a name="424" href="#424">424</a>     <strong>public</strong> <strong>void</strong> setFunctionContext(<a href="../../org/jaxen/FunctionContext.html">FunctionContext</a> functionContext)
<a name="425" href="#425">425</a>     {
<a name="426" href="#426">426</a>         getContextSupport().setFunctionContext(functionContext);
<a name="427" href="#427">427</a>     }
<a name="428" href="#428">428</a> 
<a name="429" href="#429">429</a>     <em>/**</em><em> Set a &lt;code>VariableContext&lt;/code> for use with this XPath</em>
<a name="430" href="#430">430</a> <em>     *  expression.</em>
<a name="431" href="#431">431</a> <em>     *</em>
<a name="432" href="#432">432</a> <em>     *  &lt;p></em>
<a name="433" href="#433">433</a> <em>     *  A &lt;code>VariableContext&lt;/code> is responsible for resolving</em>
<a name="434" href="#434">434</a> <em>     *  all variables referenced within the expression.</em>
<a name="435" href="#435">435</a> <em>     *  &lt;/p></em>
<a name="436" href="#436">436</a> <em>     *</em>
<a name="437" href="#437">437</a> <em>     *  @param variableContext The &lt;code>VariableContext&lt;/code> to</em>
<a name="438" href="#438">438</a> <em>     *         install for this expression</em>
<a name="439" href="#439">439</a> <em>     *</em>
<a name="440" href="#440">440</a> <em>     *  @see VariableContext</em>
<a name="441" href="#441">441</a> <em>     *  @see VariableContext#getVariableValue</em>
<a name="442" href="#442">442</a> <em>     */</em>
<a name="443" href="#443">443</a>     <strong>public</strong> <strong>void</strong> setVariableContext(<a href="../../org/jaxen/VariableContext.html">VariableContext</a> variableContext)
<a name="444" href="#444">444</a>     {
<a name="445" href="#445">445</a>         getContextSupport().setVariableContext(variableContext);
<a name="446" href="#446">446</a>     }
<a name="447" href="#447">447</a> 
<a name="448" href="#448">448</a>     <em>/**</em><em> Retrieve the &lt;code>NamespaceContext&lt;/code> used by this XPath</em>
<a name="449" href="#449">449</a> <em>     *  expression.</em>
<a name="450" href="#450">450</a> <em>     *</em>
<a name="451" href="#451">451</a> <em>     *  &lt;p></em>
<a name="452" href="#452">452</a> <em>     *  A &lt;code>NamespaceContext&lt;/code> is responsible for mapping</em>
<a name="453" href="#453">453</a> <em>     *  prefixes used within the expression to namespace URIs.</em>
<a name="454" href="#454">454</a> <em>     *  &lt;/p></em>
<a name="455" href="#455">455</a> <em>     *</em>
<a name="456" href="#456">456</a> <em>     *  &lt;p></em>
<a name="457" href="#457">457</a> <em>     *  If this XPath expression has not previously had a &lt;code>NamespaceContext&lt;/code></em>
<a name="458" href="#458">458</a> <em>     *  installed, a new default &lt;code>NamespaceContext&lt;/code> will be created,</em>
<a name="459" href="#459">459</a> <em>     *  installed and returned.</em>
<a name="460" href="#460">460</a> <em>     *  &lt;/p></em>
<a name="461" href="#461">461</a> <em>     *</em>
<a name="462" href="#462">462</a> <em>     *  @return the &lt;code>NamespaceContext&lt;/code> used by this expression</em>
<a name="463" href="#463">463</a> <em>     *</em>
<a name="464" href="#464">464</a> <em>     *  @see NamespaceContext</em>
<a name="465" href="#465">465</a> <em>     */</em>
<a name="466" href="#466">466</a>     <strong>public</strong> <a href="../../org/jaxen/NamespaceContext.html">NamespaceContext</a> getNamespaceContext()
<a name="467" href="#467">467</a>     {
<a name="468" href="#468">468</a>         <strong>return</strong> getContextSupport().getNamespaceContext();
<a name="469" href="#469">469</a>     }
<a name="470" href="#470">470</a> 
<a name="471" href="#471">471</a>     <em>/**</em><em> Retrieve the &lt;code>FunctionContext&lt;/code> used by this XPath</em>
<a name="472" href="#472">472</a> <em>     *  expression.</em>
<a name="473" href="#473">473</a> <em>     *</em>
<a name="474" href="#474">474</a> <em>     *  &lt;p></em>
<a name="475" href="#475">475</a> <em>     *  A &lt;code>FunctionContext&lt;/code> is responsible for resolving</em>
<a name="476" href="#476">476</a> <em>     *  all function calls used within the expression.</em>
<a name="477" href="#477">477</a> <em>     *  &lt;/p></em>
<a name="478" href="#478">478</a> <em>     *</em>
<a name="479" href="#479">479</a> <em>     *  &lt;p></em>
<a name="480" href="#480">480</a> <em>     *  If this XPath expression has not previously had a &lt;code>FunctionContext&lt;/code></em>
<a name="481" href="#481">481</a> <em>     *  installed, a new default &lt;code>FunctionContext&lt;/code> will be created,</em>
<a name="482" href="#482">482</a> <em>     *  installed and returned.</em>
<a name="483" href="#483">483</a> <em>     *  &lt;/p></em>
<a name="484" href="#484">484</a> <em>     *</em>
<a name="485" href="#485">485</a> <em>     *  @return the &lt;code>FunctionContext&lt;/code> used by this expression</em>
<a name="486" href="#486">486</a> <em>     *</em>
<a name="487" href="#487">487</a> <em>     *  @see FunctionContext</em>
<a name="488" href="#488">488</a> <em>     */</em>
<a name="489" href="#489">489</a>     <strong>public</strong> <a href="../../org/jaxen/FunctionContext.html">FunctionContext</a> getFunctionContext()
<a name="490" href="#490">490</a>     {
<a name="491" href="#491">491</a>         <strong>return</strong> getContextSupport().getFunctionContext();
<a name="492" href="#492">492</a>     }
<a name="493" href="#493">493</a> 
<a name="494" href="#494">494</a>     <em>/**</em><em> Retrieve the &lt;code>VariableContext&lt;/code> used by this XPath</em>
<a name="495" href="#495">495</a> <em>     *  expression.</em>
<a name="496" href="#496">496</a> <em>     *</em>
<a name="497" href="#497">497</a> <em>     *  &lt;p></em>
<a name="498" href="#498">498</a> <em>     *  A &lt;code>VariableContext&lt;/code> is responsible for resolving</em>
<a name="499" href="#499">499</a> <em>     *  all variables referenced within the expression.</em>
<a name="500" href="#500">500</a> <em>     *  &lt;/p></em>
<a name="501" href="#501">501</a> <em>     *</em>
<a name="502" href="#502">502</a> <em>     *  &lt;p></em>
<a name="503" href="#503">503</a> <em>     *  If this XPath expression has not previously had a &lt;code>VariableContext&lt;/code></em>
<a name="504" href="#504">504</a> <em>     *  installed, a new default &lt;code>VariableContext&lt;/code> will be created,</em>
<a name="505" href="#505">505</a> <em>     *  installed and returned.</em>
<a name="506" href="#506">506</a> <em>     *  &lt;/p></em>
<a name="507" href="#507">507</a> <em>     *  </em>
<a name="508" href="#508">508</a> <em>     *  @return the &lt;code>VariableContext&lt;/code> used by this expression</em>
<a name="509" href="#509">509</a> <em>     *</em>
<a name="510" href="#510">510</a> <em>     *  @see VariableContext</em>
<a name="511" href="#511">511</a> <em>     */</em>
<a name="512" href="#512">512</a>     <strong>public</strong> <a href="../../org/jaxen/VariableContext.html">VariableContext</a> getVariableContext()
<a name="513" href="#513">513</a>     {
<a name="514" href="#514">514</a>         <strong>return</strong> getContextSupport().getVariableContext();
<a name="515" href="#515">515</a>     }
<a name="516" href="#516">516</a>     
<a name="517" href="#517">517</a>     
<a name="518" href="#518">518</a>     <em>/**</em><em> Retrieve the root expression of the internal</em>
<a name="519" href="#519">519</a> <em>     *  compiled form of this XPath expression.</em>
<a name="520" href="#520">520</a> <em>     *</em>
<a name="521" href="#521">521</a> <em>     *  &lt;p></em>
<a name="522" href="#522">522</a> <em>     *  Internally, Jaxen maintains a form of Abstract Syntax</em>
<a name="523" href="#523">523</a> <em>     *  Tree (AST) to represent the structure of the XPath expression.</em>
<a name="524" href="#524">524</a> <em>     *  This is normally not required during normal consumer-grade</em>
<a name="525" href="#525">525</a> <em>     *  usage of Jaxen.  This method is provided for hard-core users</em>
<a name="526" href="#526">526</a> <em>     *  who wish to manipulate or inspect a tree-based version of</em>
<a name="527" href="#527">527</a> <em>     *  the expression.</em>
<a name="528" href="#528">528</a> <em>     *  &lt;/p></em>
<a name="529" href="#529">529</a> <em>     *</em>
<a name="530" href="#530">530</a> <em>     *  @return the root of the AST of this expression</em>
<a name="531" href="#531">531</a> <em>     */</em>
<a name="532" href="#532">532</a>     <strong>public</strong> <a href="../../org/jaxen/expr/Expr.html">Expr</a> getRootExpr() 
<a name="533" href="#533">533</a>     {
<a name="534" href="#534">534</a>         <strong>return</strong> xpath.getRootExpr();
<a name="535" href="#535">535</a>     }
<a name="536" href="#536">536</a>     
<a name="537" href="#537">537</a>     <em>/**</em><em> Return the original expression text.</em>
<a name="538" href="#538">538</a> <em>     *</em>
<a name="539" href="#539">539</a> <em>     *  @return the normalized XPath expression string</em>
<a name="540" href="#540">540</a> <em>     */</em>
<a name="541" href="#541">541</a>     <strong>public</strong> String toString()
<a name="542" href="#542">542</a>     {
<a name="543" href="#543">543</a>         <strong>return</strong> <strong>this</strong>.exprText;
<a name="544" href="#544">544</a>     }
<a name="545" href="#545">545</a> 
<a name="546" href="#546">546</a>     <em>/**</em><em> Returns a string representation of the parse tree.</em>
<a name="547" href="#547">547</a> <em>     *</em>
<a name="548" href="#548">548</a> <em>     *  @return a string representation of the parse tree.</em>
<a name="549" href="#549">549</a> <em>     */</em>
<a name="550" href="#550">550</a>     <strong>public</strong> String debug()
<a name="551" href="#551">551</a>     {
<a name="552" href="#552">552</a>         <strong>return</strong> <strong>this</strong>.xpath.toString();
<a name="553" href="#553">553</a>     }
<a name="554" href="#554">554</a>     
<a name="555" href="#555">555</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="556" href="#556">556</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="557" href="#557">557</a>     <em class="comment">//     Implementation methods</em>
<a name="558" href="#558">558</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="559" href="#559">559</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="560" href="#560">560</a> 
<a name="561" href="#561">561</a>     
<a name="562" href="#562">562</a>     <em>/**</em><em> Create a {@link Context} wrapper for the provided</em>
<a name="563" href="#563">563</a> <em>     *  implementation-specific object.</em>
<a name="564" href="#564">564</a> <em>     *</em>
<a name="565" href="#565">565</a> <em>     *  @param node the implementation-specific object </em>
<a name="566" href="#566">566</a> <em>     *         to be used as the context</em>
<a name="567" href="#567">567</a> <em>     *</em>
<a name="568" href="#568">568</a> <em>     *  @return a &lt;code>Context&lt;/code> wrapper around the object</em>
<a name="569" href="#569">569</a> <em>     */</em>
<a name="570" href="#570">570</a>     <strong>protected</strong> <a href="../../org/jaxen/Context.html">Context</a> getContext(Object node)
<a name="571" href="#571">571</a>     {
<a name="572" href="#572">572</a>         <strong>if</strong> ( node instanceof Context )
<a name="573" href="#573">573</a>         {
<a name="574" href="#574">574</a>             <strong>return</strong> (Context) node;
<a name="575" href="#575">575</a>         }
<a name="576" href="#576">576</a> 
<a name="577" href="#577">577</a>         <a href="../../org/jaxen/Context.html">Context</a> fullContext = <strong>new</strong> <a href="../../org/jaxen/Context.html">Context</a>( getContextSupport() );
<a name="578" href="#578">578</a> 
<a name="579" href="#579">579</a>         <strong>if</strong> ( node instanceof List )
<a name="580" href="#580">580</a>         {
<a name="581" href="#581">581</a>             fullContext.setNodeSet( (List) node );
<a name="582" href="#582">582</a>         }
<a name="583" href="#583">583</a>         <strong>else</strong>
<a name="584" href="#584">584</a>         {
<a name="585" href="#585">585</a>             List list = <strong>new</strong> <a href="../../org/jaxen/util/SingletonList.html">SingletonList</a>(node);
<a name="586" href="#586">586</a>             fullContext.setNodeSet( list );
<a name="587" href="#587">587</a>         }
<a name="588" href="#588">588</a> 
<a name="589" href="#589">589</a>         <strong>return</strong> fullContext;
<a name="590" href="#590">590</a>     }
<a name="591" href="#591">591</a> 
<a name="592" href="#592">592</a>     <em>/**</em><em> Retrieve the {@link ContextSupport} aggregation of</em>
<a name="593" href="#593">593</a> <em>     *  &lt;code>NamespaceContext&lt;/code>, &lt;code>FunctionContext&lt;/code>,</em>
<a name="594" href="#594">594</a> <em>     *  &lt;code>VariableContext&lt;/code>, and {@link Navigator}.</em>
<a name="595" href="#595">595</a> <em>     *</em>
<a name="596" href="#596">596</a> <em>     *  @return aggregate &lt;code>ContextSupport&lt;/code> for this</em>
<a name="597" href="#597">597</a> <em>     *          XPath expression</em>
<a name="598" href="#598">598</a> <em>     */</em>
<a name="599" href="#599">599</a>     <strong>protected</strong> <a href="../../org/jaxen/ContextSupport.html">ContextSupport</a> getContextSupport()
<a name="600" href="#600">600</a>     {
<a name="601" href="#601">601</a>         <strong>if</strong> ( support == <strong>null</strong> )
<a name="602" href="#602">602</a>         {
<a name="603" href="#603">603</a>             support = <strong>new</strong> <a href="../../org/jaxen/ContextSupport.html">ContextSupport</a>( 
<a name="604" href="#604">604</a>                 createNamespaceContext(),
<a name="605" href="#605">605</a>                 createFunctionContext(),
<a name="606" href="#606">606</a>                 createVariableContext(),
<a name="607" href="#607">607</a>                 getNavigator() 
<a name="608" href="#608">608</a>             );
<a name="609" href="#609">609</a>         }
<a name="610" href="#610">610</a> 
<a name="611" href="#611">611</a>         <strong>return</strong> support;
<a name="612" href="#612">612</a>     }
<a name="613" href="#613">613</a> 
<a name="614" href="#614">614</a>     <em>/**</em><em> Retrieve the XML object-model-specific {@link Navigator} </em>
<a name="615" href="#615">615</a> <em>     *  for us in evaluating this XPath expression.</em>
<a name="616" href="#616">616</a> <em>     *</em>
<a name="617" href="#617">617</a> <em>     *  @return the implementation-specific &lt;code>Navigator&lt;/code></em>
<a name="618" href="#618">618</a> <em>     */</em>
<a name="619" href="#619">619</a>     <strong>public</strong> <a href="../../org/jaxen/Navigator.html">Navigator</a> getNavigator()
<a name="620" href="#620">620</a>     {
<a name="621" href="#621">621</a>         <strong>return</strong> navigator;
<a name="622" href="#622">622</a>     }
<a name="623" href="#623">623</a>     
<a name="624" href="#624">624</a>     
<a name="625" href="#625">625</a> 
<a name="626" href="#626">626</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="627" href="#627">627</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="628" href="#628">628</a>     <em class="comment">//     Factory methods for default contexts</em>
<a name="629" href="#629">629</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="630" href="#630">630</a>     <em class="comment">// ------------------------------------------------------------</em>
<a name="631" href="#631">631</a> 
<a name="632" href="#632">632</a>     <em>/**</em><em> Create a default &lt;code>FunctionContext&lt;/code>.</em>
<a name="633" href="#633">633</a> <em>     *</em>
<a name="634" href="#634">634</a> <em>     *  @return a default &lt;code>FunctionContext&lt;/code></em>
<a name="635" href="#635">635</a> <em>     */</em>
<a name="636" href="#636">636</a>     <strong>protected</strong> <a href="../../org/jaxen/FunctionContext.html">FunctionContext</a> createFunctionContext()
<a name="637" href="#637">637</a>     {
<a name="638" href="#638">638</a>         <strong>return</strong> XPathFunctionContext.getInstance();
<a name="639" href="#639">639</a>     }
<a name="640" href="#640">640</a>     
<a name="641" href="#641">641</a>     <em>/**</em><em> Create a default &lt;code>NamespaceContext&lt;/code>.</em>
<a name="642" href="#642">642</a> <em>     *</em>
<a name="643" href="#643">643</a> <em>     *  @return a default &lt;code>NamespaceContext&lt;/code> instance</em>
<a name="644" href="#644">644</a> <em>     */</em>
<a name="645" href="#645">645</a>     <strong>protected</strong> <a href="../../org/jaxen/NamespaceContext.html">NamespaceContext</a> createNamespaceContext()
<a name="646" href="#646">646</a>     {
<a name="647" href="#647">647</a>         <strong>return</strong> <strong>new</strong> <a href="../../org/jaxen/SimpleNamespaceContext.html">SimpleNamespaceContext</a>();
<a name="648" href="#648">648</a>     }
<a name="649" href="#649">649</a>     
<a name="650" href="#650">650</a>     <em>/**</em><em> Create a default &lt;code>VariableContext&lt;/code>.</em>
<a name="651" href="#651">651</a> <em>     *</em>
<a name="652" href="#652">652</a> <em>     *  @return a default &lt;code>VariableContext&lt;/code> instance</em>
<a name="653" href="#653">653</a> <em>     */</em>
<a name="654" href="#654">654</a>     <strong>protected</strong> <a href="../../org/jaxen/VariableContext.html">VariableContext</a> createVariableContext()
<a name="655" href="#655">655</a>     {
<a name="656" href="#656">656</a>         <strong>return</strong> <strong>new</strong> <a href="../../org/jaxen/SimpleVariableContext.html">SimpleVariableContext</a>();
<a name="657" href="#657">657</a>     }
<a name="658" href="#658">658</a>     
<a name="659" href="#659">659</a>     <em>/**</em><em> Select all nodes that match this XPath</em>
<a name="660" href="#660">660</a> <em>     *  expression on the given Context object. </em>
<a name="661" href="#661">661</a> <em>     *  If multiple nodes match, multiple nodes</em>
<a name="662" href="#662">662</a> <em>     *  will be returned in document-order, as defined by the XPath</em>
<a name="663" href="#663">663</a> <em>     *  specification. If the expression selects a non-node-set</em>
<a name="664" href="#664">664</a> <em>     *  (i.e. a number, boolean, or string) then a List</em>
<a name="665" href="#665">665</a> <em>     *  containing just that one object is returned.</em>
<a name="666" href="#666">666</a> <em>     *  &lt;/p></em>
<a name="667" href="#667">667</a> <em>     *</em>
<a name="668" href="#668">668</a> <em>     * @param context the Context which gets evaluated</em>
<a name="669" href="#669">669</a> <em>     *</em>
<a name="670" href="#670">670</a> <em>     * @return the node-set of all items selected</em>
<a name="671" href="#671">671</a> <em>     *          by this XPath expression</em>
<a name="672" href="#672">672</a> <em>     * @throws JaxenException if an XPath error occurs during expression evaluation</em>
<a name="673" href="#673">673</a> <em>     *</em>
<a name="674" href="#674">674</a> <em>     */</em>
<a name="675" href="#675">675</a>     <strong>protected</strong> List selectNodesForContext(<a href="../../org/jaxen/Context.html">Context</a> context) throws JaxenException
<a name="676" href="#676">676</a>     {
<a name="677" href="#677">677</a>         List list = <strong>this</strong>.xpath.asList( context );
<a name="678" href="#678">678</a>         <strong>return</strong> list;
<a name="679" href="#679">679</a>         
<a name="680" href="#680">680</a>     }
<a name="681" href="#681">681</a>  
<a name="682" href="#682">682</a> 
<a name="683" href="#683">683</a>     <em>/**</em><em> Return only the first node that is selected by this XPath</em>
<a name="684" href="#684">684</a> <em>     *  expression.  If multiple nodes match, only one node will be</em>
<a name="685" href="#685">685</a> <em>     *  returned. The selected node will be the first</em>
<a name="686" href="#686">686</a> <em>     *  selected node in document-order, as defined by the XPath</em>
<a name="687" href="#687">687</a> <em>     *  specification. If the XPath expression selects a double,</em>
<a name="688" href="#688">688</a> <em>     *  String, or boolean, then that object is returned.</em>
<a name="689" href="#689">689</a> <em>     *  &lt;/p></em>
<a name="690" href="#690">690</a> <em>     *</em>
<a name="691" href="#691">691</a> <em>     * @param context the Context against which this expression is evaluated</em>
<a name="692" href="#692">692</a> <em>     *</em>
<a name="693" href="#693">693</a> <em>     * @return the first node in document order of all nodes selected</em>
<a name="694" href="#694">694</a> <em>     *          by this XPath expression</em>
<a name="695" href="#695">695</a> <em>     * @throws JaxenException if an XPath error occurs during expression evaluation</em>
<a name="696" href="#696">696</a> <em>     *</em>
<a name="697" href="#697">697</a> <em>     *  @see #selectNodesForContext</em>
<a name="698" href="#698">698</a> <em>     */</em>
<a name="699" href="#699">699</a>     <strong>protected</strong> Object selectSingleNodeForContext(<a href="../../org/jaxen/Context.html">Context</a> context) throws JaxenException
<a name="700" href="#700">700</a>     {
<a name="701" href="#701">701</a>         List results = selectNodesForContext( context );
<a name="702" href="#702">702</a> 
<a name="703" href="#703">703</a>         <strong>if</strong> ( results.isEmpty() )
<a name="704" href="#704">704</a>         {
<a name="705" href="#705">705</a>             <strong>return</strong> <strong>null</strong>;
<a name="706" href="#706">706</a>         }
<a name="707" href="#707">707</a> 
<a name="708" href="#708">708</a>         <strong>return</strong> results.get( 0 );
<a name="709" href="#709">709</a>     }
<a name="710" href="#710">710</a>     
<a name="711" href="#711">711</a> }
</pre>
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